There was a new version of the original Myst for the iPad that was promoted recently. For sure hours of fun and headaches in that one.

FTL for iPad. Just a brilliant game through and through that makes the transition from desktop to tablet perfectly.

https://apps.apple.com/us/app/dicey-dungeons/id1368013995

EDIT:

Hit the comment button early by accident

Anyway it's a turn-based dungeon crawler where your actions cost dice rolls. Multiple characters with very different gameplay mechanics, all in support of the core loop.

I highly recommend it. Probs put over 100 hours into this bad boi

Check out Pocket City 2 if you like city builders. It threads the needle of depth, but also acknowledging the limitations of a touchscreen interface.

I looooove many of the Glitch games, like Forever Lost. If you haven't played it, The Room is also a classic.

Stardew Valley! Time killer and loving it while traveling.

if you like puzzle games, the Rusty Lake/Cube Escape series of games are pretty cool. They give off a sort of Twin Peaks vibe, if you’re into that.

I don't normally use iOS devices so when I borrow my friend's ancient iPad it is to play a couple digital boardgame implementations that are available for iOS but not Android: Finished!, Dead Man's Draw and Zombie Dice. So I guess those are my favorites. Probably not very relevant for most :)

Finished! in particular is pretty addictive and very satisfying when you finally get that win.

Is 'There Is No Game' compatible with your iPad? That's been one of my favorites!

Papers, Please. I find having a touch screen for it makes the game more immersive.

I wanted to recommend DOS2 :( but I’m pretty sure that the 9th gen is enough to run all Baldur’s Gate games, and they’re great too (I had this iPad before my M2 and they worked well)!

The Room games are great puzzle/escape room type things where you use the screen to rotate items, flip switches, drag things, etc; it's very tactile and clearly built for a touch screen. Each one takes about 2-4 hours.